【TED】Alan Eustace。我從平流層一躍而下。我從平流層躍起，我是這樣做的（I leapt from the stratosphere. Here's how I did it | Alan Eustace) (【TED】Alan Eustace: I leapt from the stratosphere. Here's how I did it (I leapt from the stratosphere. Here's how I did it | Alan Eustace))